The present invention relates to television systems and more particularly to television systems wherein signals from two or more sources are mixed. For the mixing, a unit called a special effects generator is used. In order for this unit to operate properly, it is very important that these signals are timed very accurately with respect to one another at the point in which they enter the special effects generator. Specifically, if the color burst of one signal does not have the same phase as the other, a difference in hue will result. Similarily, if the synchronizing signals of one television signal are out of phase with one another, a shift in the horizontal position of the picture created by one signal relative to that of the other will result. To prevent both of these difficulties an exact phase match is necessary. A vectorscope is usually used for this purpose. The color bursts of each television signal are applied in turn to the input of the vectorscope. For each, the position of a spot on the vectorscope display is noted. When the spots resulting from the two signals are in the same position the color bursts of the two signals are phase-matched. Similarly, the horizontal synchronizing signals can be applied to the vectorscope and their relative phase adjusted to meet the same criterion. In this known method, the spots on the vectorscope whose position is indicative of the phase of the applied signals are not visible simultaneously. Further, although the results obtained are extremely accurate the vectorscope is very expensive, not owned by many small studios, and is usually not available in a portable television system.
As a prior art statement, application wishes to say that he is not aware at this time of any method or system for phase matching signals from a plurality of television sources, closer to the present invention than the method and system utilizing a vectorscope as described above.